Porter, Jack R. / Woods, R. Grant, Extensions and Absolutes of Hausdorff Spaces. Softcover reprint of the original 1st ed. 1988. 856 pp. (Springer-Verlag New York Inc., US) ＜M25-18080＞

Buechi, J. Richard / Siefkes, Dirk (ed.), Finite Automata, Their Algebras and Grammars : Towards a Theory of Formal Expressions. Softcover reprint of the original 1st ed. 1989. 316 pp. (Springer-Verlag New York Inc., US) ＜M25-18101＞